Response of some scolytids and their predators to ethanol and 4-allylanisole in pine forests of central Oregon

Lindgren multiple funnel traps were set up in pine forests of central Oregon to determine the response of scolytid bark beetles to ethanol and 4-allylanisole (4AA). Traps were baited with two release rates of ethanol (4.5 or 41.4 mg/hr) and three release rates of 4AA (0, 0.6, or 4.3 mg/hr) in a 2 x 3 factorial design. All traps also released a 1:1 mixture of alpha- and beta-pinene at 11.4 mg/hr. Of 13,396 scolytids caught, Dendroctonus valens made up 60%, Hylurgops spp. 18.5%, Ips spp. 16%, Hylastes spp. 1.8%, Ganthotrichus retusus 0.9%, and bark beetle predators another 2.8%. Increasing the release rate of ethanol in the absence of 4AA increased the number of most scolytid species caught by 1.5-3.7 times, confirming its role as an attractant. Ips latidens, Temnochila chlorodia, and clerid predators were exceptions and did not show a response to higher ethanol release rates. Release of 4AA at the lowest rate inhibited attraction of most scolytids, with a significant reduction in G. retusus, Hylastes macer, and Hylurgops porosus when compared to traps without 4AA. A high release rate of 4AA further inhibited responses for most beetles compared to low 4AA. Seven species were significantly deterred by high 4AA, including the latter three, and Hylastes longicollis, Hylastes nigrinus, Hylurgops reticulatus, and Ips latidens. Exceptions include Hylurgops subcostulatus, which was significantly attracted to both low and high 4AA, and I. pini, which was attracted to low and high 4AA in combination with low ethanol, but unaffected by either release of 4AA with high ethanol. Dendroctonus valens was significantly attracted to low 4AA and unaffected by high 4AA. Predators appeared to be less inhibited by 4AA than most bark beetles. Although 4AA can deter the attraction of some secondary bark beetles to ethanol in combination with alpha- and beta-pinene, this inhibition could be weakened for certain species by increasing ethanol release rates. 4-Allylanisole may have some utility for managing the behavior of secondary bark beetles sensitive to this compound.

Seasonal and tissue variation in taxane concentrations of Taxus brevifolia

Analysis of seven taxanes: taxol, baccatin III, 10-deacetyltaxol, 10-deacetylbaccatin III, 7-xylosyl-10-deacetyltaxol, cephalomannine and brevifoliol in extracts from bark and foliage of pacific yew (Taxus brevifolia) showed a gradient of decreasing concentration from stem base to branch tip. This decrease is attributed to the generally higher concentration of taxanes in the phloem tissue and the decrease in inner bark thickness from base to branch tip. Analysis of taxanes extracted from stem bark and needles sampled over a growing season showed that most taxane concentrations were significantly lower in the needles than in the bark. Typically, taxane concentrations in bark increased from May through August; whereas, in needles, concentrations changed little during that period. Two exceptions were baccatin III, which in the summer reached levels equivalent to bark, and brevifoliol which increased from March to August, reaching levels in needles nine times greater than bark.